1. Field of Invention
This invention relates to sailing apparatus, specifically an elevated sailing apparatus.
2. Description of Prior Art
Modern high-speed sailing can be characterized by the need for a righting moment to counter the heeling moment that is caused by the aerodynamic force developed by the sail acting on the mast and rigging. Multiple hulls or heavily ballasted keels are two approaches to providing the righting moment. Recently people have started using kites to reduce the heeling moment. The aerodynamic force generated by the kite acts near the water line of the vessel, rather than part way up the mast. However, these kites usually have two (or four) kite lines, and require constant attention to control. They may be damaged and are difficult to re-launch should they land in the water. U.S. Pat. No. 5,366,182 to Roeseler (1994) and U.S. Pat. No. 4,708,078 (1987) to Legainoux et al, describes such kite systems. Neither addresses the requirement of constant attention to control.
The Veazy U.S. Pat. No. 4,497,272 (1985) describes “mastless sails” which are applicable to low-speed and downwind sailing. It does not have the features necessary to achieve the high lift-to-drag ratio required for high-speed sailing. In particular it describes the use of a balloon rather than a streamlined blimp, and the use of a low aspect-ratio kite or spinnaker rather than a high aspect-ratio wing or sail. Control is only described in terms of sheets. The use of aerodynamic stabilizers, a single tether line, and electronic control systems are not described.